Is "a wide range of features" singular or plural?

In the office, we've been having a discussion about the grammar in a sentence and have differing opinions about what is right and what is wrong... It is a very minor issue but is still bugging me :)

The sentence in question is:

A wide range of features is available.

Which sounds more natural to me if it is written as:

A wide range of features are available.

The justification for it is that the "is" is referring to the "wide range of features" as a whole rather than just the "features".

I was just about getting used to it when I decided to substitute a different word instead of "features". I just can't get my head around something like:

A wide range of sausages is available.

Further to this, if I substitute "a wide range of" with "various" then it has to be are.

Which one is right?

Edit: Thanks for all of the responses. I didn't expect to open up such a can of worms but now I understand the technicalities. I still prefer are in this case though :)

“A wide range of features is available” is more ‘technically correct’ according to traditional prescriptive grammar, and arguably more logical.

Both forms are completely idiomatically acceptable, though; Google n-grams suggests that as of the 90’s, they were roughly equally common:

That shows just this specific example, which appears only in recent decades, but there are a host of other similar constructions, going back for centuries, and in many levels of writing, not just casual speech. So well-informed modern grammars agree, both forms are completely correct; go with whatever you feel flows best!

Edit: Actually, in contexts like yours, are is probably rather more common than that graph might suggest. Looking more closely, of the results for “range of features is”, quite a lot are in contexts like “The range of features is typically quite large…”, where “are” wouldn’t make sense — the predicate unambiguously applies to the range, not to the individual features. I can’t think of a corpus search that would weed out such cases; on a very rough perusal of Google Books results, I’d guesstimate that in contexts like yours where either is idiomatic (eg “…a remarkable range of features is/are visible…”), the are form is maybe about twice as common as the is. (Thanks to @FumbleFingers for pointing this out in comments.)

Edit: as comments on other answers show, the two versions aren’t always interchangeable; one can certainly come up with examples where only one or the other is idiomatic. But in this specific example, both are quite fine, as the n-grams search above and more in-depth searching along similar lines illustrate.

I can't go with the mavens on this one. By strict rules of grammar it's obviously right to say is is correct. But I'm sure we all know that nearly everyone uses are in this context without giving it a second thought. And of the one's that don't, I bet many do so with misgivings.

So it really depends on your definition of 'right'. Assuming we're not interested in any moral overtones of righteousness, I would say it's 'right' in linguistic terms to fall into line with the overwhelmingly more prevalent usage. On the grounds that language itself couldn't really work as a means of communication if we didn't normally honour that principle.

The verb should match the noun without the prepositional phrase. In this case, drop "of features" and you have "A wide range is/are available." Since range is singular, you would go with is, not are.

The correct sentence would read:

A wide range of features is available.

This is because the verb must modify the subject of the sentence. Removing the prepositional phrase of features makes this rule more apparent:

A wide range is available.